Holder for use in reclaiming broken cutting tools



March 15, 1949. J, HENGSTLER 2,464,574

HOLDER FOR USE IN RECLAIMING BROKEN CUTTING-TOOLS Original Filed Nov.25, 1944 2 Sheds-Sheet 1 March 15, 194g. HENGSTLER 2,464,574

HOLDER FOR USE IN RECLAIMING BROKEN CUTTING-TOOLS Original Filed Nov.25, 1944 2 Sheets-Sheet 2 WITNESSES INVENTOR;

BY flaw/W A TTORNEYS.

Jobizfienysfleg I Patented Mar. 15, 1949 r HOLDER FOR USE IN RECLAIMINGBROKEN CUTTING TOOLS John Hengstler, Altoona, Pa., assignor to ThePennsylvania Railroad Company, Philadelphia, Pa., a corporation ofPennsylvania.

Original application November 23, 1944, Serial Divided and thisapplication December 27, 1945, Serial No. 637,434

This invention has general reference to the restoration of broken, orotherwise damaged, metal articles to their former state or condition ofusefulness; while it relates more particularly to the reclaiming ofbroken milling-cutters or the like and the instant case is a division ofmy prior application Serial Number 564,864, filed November 23, 1944.

Heretofore attempts have been made to reclaim broken slabmilling-cutters, but such attempts have proven unsatisfactory owing tothe reduction in the requisite hardness, so vital to successful usage ofsuch cutters, and their inability to hold a good cutting edge. Morespecifically slab milling-cutters frequently break into two, or more,pieces during milling of the active face, and I have endeavored torepair the same with low temperature melting alloy welding wire andflux, in the manner prescribed by manufacturers thereof, with the resultthat the cutter became softened during the reclamation process to suchan extent that it would not hold a good cutting edge when re-sharpened.

The primary aim of this invention is to provide a novel holder meanswhereby the above noted disadvantages are positively overcome. Anotheraim is to effect reclamation of broken milling-cutters, and otherferrous articles, which can be carried out with pre-assurance the saidcutter, or other article, will be definitely restored to serviceablecondition.

A further aim of this invention is to provide a novel holder or jig foruse in the reclamation of the broken parts of a high speed steelmillingcutter by heat-treatment and welding, whereby said parts areeffectively and evenly integrated together at the junctures.

While the foregoing stated aims are indicative of the objects of thisinvention, others with ancillary advantages will be evident to thoseskilled in the art upon a full understanding of the holder meanshereinafter disclosed; but it is to be likewise appreciated that saidinvention is susceptible of variation and modification coming equallywithin the terms and scope of the concluding claims.

In the accompanying drawings:

Fig. 1 is a top plan view of a convenient means or jig, preferablyadapted for holding the broken parts of a spiral milling-cutter togetherduring re-integration of said broken parts into unified assembly.

Fig. 2 is an elevation of the same, or as viewed from below Fig. 1.

Fig. 3 is a vertical section, taken approximately as indicated by theangled arrows III-III in Fig. 2; and,

2 Claims. (Cl. 113-99) Fig. 4 is a similar section taken on the planeIV-IV of Figs. 1 and 3.

In describing the form of this invention exemplified in the two sheetsof drawings herewith, specific terms will be employed for the sake ofclarity, but it is to be understood the scope of said invention is notthereby limited; each such term being intended to embrace all reasonableequivalents which perform the same function for an analogous purpose.

In carrying out my invention as adapted for the reclamation of brokenslab milling-cutters, which it is here remarked usually split lengthwiseinto two or three parts. As a concrete example, and assuming that aconventional steel milling-cutter eight and one-quarter inches long,having an outside diameter of five inches with a bore of two andone-half inches diameter, to have been split lengthwise at approximatelydiametrically-opposed points, indicated by irregular lines to definefracture surfaces 1, 1, Figs. 3 and 4, into two parts 8, 8. I first takethe two parts 8, 8 and remove all grease and other foreign substancestherefrom; and then apply or coat the fracture surfaces 1, 1 only with asuitable flux, and place said two parts in a gas furnace, for example,such furnace having a heat about 1200 F. After being in the furnace forabout twenty minutes, to volatilize the flux, the two parts 8, 8 arewithdrawn and an appropriate welding deposit heat applied entirely overthe fracture faces 1, with incidental driving of the volatilized fluxfrom off said fracture surfaces; whereupon the two parts 8, 8 are placedwith the respective fracture surfaces 1, 1, in mutual confrontingengagement, and tack welded together, preferably at the ends, to preventrelative separation or movement out of registration; all as set forth inmy hereinbefore referred to prior application Serial No. 564,864.

The re-assembled cutter, hereinafter comprehensively designated 9, isnow placed in the jig, referred to generally as id, now to be described.This jig Ill conveniently, although not essentially, comprises abox-like structure including end and side walls ll, i2 respectively, allof rectangular contour. The end walls H are vertically spaced with therectangularly-related side walls l2 united thereto by fillet-welds l3intermediate the opposedly-beveled edges 14 of the 1 walls l2 and therelatively confronting vertical side edges of the end walls H, as bestunderstood on an examination of Figs; 1 and 2. The jig Ii! also includesa bottom I, Fig. 3, consisting of two plate elements "5, l1, preferablydisposed at an angle of ninety-degrees to insure the cutter 9 beingproperly centralized when placed therein and said plate elements arerespectively united to the lower edges of the side walls Ii by filletwelds l8, aswwelleas-to' vonelanotherby a similar weld l8. Opposedapertures or peep-holes iii are provided in the side walls l2. Inaddition, it will be seen the jig end walls II are each formed A with anupward projection or lug 32L, .havingpanw aperture 22 therethrough, andwhereby theijig' I can be lifted, carried or otherwise manipulated, whenin use.

23 designates a top or closure for the jig lt," the same being of acontour for free movementinto position between the end and sidewalls ll,

l2 respectively, while it is formedlwithsa centralembossment 24, for apurpose later explainedhl l The closure 23 is provided withdependentlom. gitudinally-spaced chocks 25, conveniently" se--' curedthereto by fillet welds 2G, for seating on the 'cuttenil, asreadily-understood from Fig-.23, more particularly.

To ecure the closure 23 ineffective engagementon topof the cutter- 9;while "the latter is in the jig HJJ I 'preierably .provide'the sidewalls with opposedupstanding projection -27; havingrectangular slots'28therethrough for passageof a cotter-or clampingkey-member 29 2 Attentionis directed-to the fact that-the horizontal-lower edge 30 of said memberseats on the closure-em bossment 24 above referred to, whereas the un- Iper" inclined: edge 3 l ofthe member 29' oo-acts with the'complemcntarily" sloped upper faces of the rectangularslots2th" Itisalso to be noted the clampingmember295 'in use, is'free of engag-ementwith-the lower=-faces--33? of the slots 28,

Wherebythe' clamping pressure is longitudinally;

directedand evenly distributed lengthwise: of

the cutter d, as/readilyunderstandable by those conversant with the art-Having describedth'e structural features of' the 1 jigelll and-uponplacement-of the tacked together. hereinbefore men tio'ned,=-it is to beparticularly noted --'that the broken *cutten fi therein; A aslongitudinahfracture"faces-l, T conveniently registemwith ithe:peep-holes- 251 whereupon the top 1 next'zinserted through "therectangular slots 231 of :the jig:v projections 2?, and. slightlydrifted*- or cclosure 223 is put-:in' place; the member 23 is soethattelittle: or very-slightclamping pressure is exertedonwthepre-heatedand assembled parts of the cutter 9;! Incidentally thisinsertion of thetacked-zbroken'parts ll into thefjigl it "is'only"resorted: rto Jor the: :purpose of I better ensuringthatzthelfracture:surfacesZ, of the respective: broken;partsf:8,lmutually=register without any 'overlapiofirtheir respectivesurrounding edges:

ThetvfjigV 10 s'conta-ining the tacked ."cutter'Q is placed'inz-ranzeleotric furnace heated to a temperature of 900 F., with thetemperature slowly raised-eat; determined interval periodsto"150 F.;-"and (SIlbSGQIlEIIC thEI'GtS' said temperature is rapidlytraisedito-2200? F. This temperature of 220Q?;:'F; is :he-ld. .for about eighteen=minutes for all-ecutters-less than three-inchesin diameter,

andflontwentyi-fourminutes for all cutters threeIncidentallmthetemperature periods;referred to inz th'epreceding-paragraphlfrom 900: F. upward-)Jaregoverned by the thicknessof the cutnoteworthy that at the 1850 Fi'heat, the weld actualz: welding-cycle;

Them. -Jig!.= -l'0= is then removed" from the electricfurnace and thekey-member 29 driven tight to clamp, and lock, the fracture faces 1 intight mutual registration; when'xsaid "jig? ill with the enclosed cutter9 "is allowed to cooldown' to a temperature of between 400 R, and 700 F.depending on the type of the steel forming the cutter When thedesirable'cooling temperature, intervening 400 F. and 700 F., is reachedthe jig Ill and enclosed cutter 93 is again placed in the electricfurnace, at a temperature of 900 F. and said temperature is then slowlyraised to 1 00 F. or 1300? F2, for aboutone-hour for the purpose ofdrawing and tempering the cutter. When the lie? lc'l' 'and cutter it arefinally removed from the furnace they are preferably allowed to cool toroom temperature; whereupon the cutter El is taken out of said jlgr andlater sharpened by grinding in the known mannerw Obviously, :a

second drawing teinpering period may bezrequi-i siteto obtain'the'proper hardness for'rthe re serves to retire fact said cutteris'restrained at four oircumfera entially spaced or opposins ipointsrbyithe partsx:

5, 37 and: 25'."

While the holder' or jig,v llrhas been-more specifically described inconnection. with there-v.

clamation of broken slab;milling-cutters, I cer:--.'

tain features thereof are of morexgeneral utility; and it'is thereforeto be understood; saidinven tion in its broader aspect-is not limitedtothe'ex act-means; shown and described.

Having thus described my inventiomrl claims-.1; 1. A holder for use inWelding brokenLmillingn-v cutters comprising:=vertically+spacedrectanguezlarlyerelated side send walls integratedxwget-her by filletwelds beveled edges of'thesidawalls and. the relatively con-frontinvertical edgesof' the end walls slottedprojectionsonthaside Walls, and:end

walls including: apertured cal i tom'of said holder comprisingtwoplateelements with intervening angle of ninety degrees, and-1said-elements being integrated together andptoxv the lower edges of theside wallshy-filletwelds; "1

a closureior the holder-in theform of a rcctangus, lar plate with anembossinent on'its' outer face andangularly dependent chocks'integratedtoiits 1 inner face; and means'forclamping the closure: to the holderwith concurrent restraintofthet.

cutter therein against relative movement.

2.The inventioniof'claim 1 wherein therclosm'e is provided withacentral-embossmenty: wherein termediatef the opposedly I opposedsideWalls of the holderhave upstand-av ing projections with vertical slotstherethrough;v wherein the clampmeans consists of a key'havs: ing aninclined upperedge; and wherein .thezkeyu' seats on theembossmentand isarranged. for operation iintermediatethe ernbossment and the upper edgesof the vertical slots aforesaid.

J GEN HE'NGSTLER.

REFERENGES :CITED- The following references are file of this patent:

U NITED. STATES PATENTS Number Name Date" 552,951 Boweri; Jan.:'14,-1896' 2,381,584 Fulleton Aug; 7, ,1945 1-5:

of record in the

